现将3个相同的红球和4个相同的白球排成一列,要使红球各不相邻,则有多少种排法?A.1 B.5 C.10 D.60

作者: rantiku 人气: - 评论: 0
问题 现将3个相同的红球和4个相同的白球排成一列,要使红球各不相邻,则有多少种排法? A.1 B.5 C.10 D.60
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答案 C
解析 要使红球各不相邻,则只需要把3个红球插入4个白球所形成的5个空档中即可,有

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